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GROUND WATER MONITORING Bedrock Two monitored wells (008-77-58 and 008 79-6; see Figure 2) are wmpleted in the Wadge Overburden (which includes the Wadge Coal). Water Levels -Levels in the wells have been measured since 1979 (Figures 4 and S). Water levels in Weli 008-77-58 showed a sharp decline from March 1979 to February 1980. A generally increasing trend is noted since with recently recorded water levels approaching the initial levels documented at this site. Water levels in Well 008-79-6 rose abruptly in 1980 and continued to show an increasing trend during the period 1981 through mid-1986, followed by a slight decreasing trend during the period 1987 through 1993. Water levels since 1993 are again shown to be increasing. The abrupt rise in 1980 is probably due to water level recovery in the Wadge Coal and overburden following cessation of mining in the vicinity of this well in 1979 or 1980. The trends from 1983 on appear to follow the general climatic trends illustrated by the flow data presented as Figures l S and 17. The data illustrated in Figures 4 and S generally indicates that the water level in the Wadge overburden varies seasonally. Recorded water levels in the spring are typically higher than in the fall. Seasonal fluctuations in both wells typically vary by as much as 6 feet Although the seasonal flucmation in Well 008-79-6 appeared to have dimwshed somewhat in the time period following 1986. The 1997 fluctuation in well 008-79-6 was somewhat greater than that recent trend, but the similar pattern seen • in the nearby alluvial well 008-AV-2 continues to demonstrate a relationship to the trends and fluctuations of Foidel Creek and the alluvium. Water level fluctuations observed during 1997 were consistent with previously established patterns at both wells. Explanations for the water level fluctuations and trends in Well 008-77-58 are not readily apparent. The water levels dropped abruptly between 1979 and 1980. The reason for the decline may be related to dewatering operations occurring during the aborted underground mining attempt at Mine No. 3 (May 79 to June 1980). Water level recoveries, however, are not neazly as abrupt although a relatively steady upward trend is evident. Within Otis long term pattern, the water level fluctuations at this well generally follow the longer term climatic trend, with slight increases noted for the wetter period 1982 through 1986 followed by a slight decrease for the dryer period 1987 through 1992. Water levels from 1992 though 1996 are again noted [o be increasing. The associated climatic patterns are again reflected in the flow data presented as Figures IS and 17. A relatively dry year occurred in 1993 but a corresponding decrease in water level is not reflected in the water level data recorded for Well 008-77- 58. A declining response is noted in the water level data for 1993 at Well 008-79-6. The typical seasonal fluctuation expected, with higher water levels in the spring and relatively lower levels in the fall, is apparent in both wells 008-77-58 and 008-79-6. Tables 6B and 7B provide period of record statistical summary information for water levels at Wells 008-77-58 and 008-79-6. Water Quality -Water quality data for the Wadge Overburden wells at Mine 3 is presented on Tables 6, 6A, 7, and 7A. Plots of period of record total dissolved solids (TDS) data for both wells are presented as Figures 6 and 7. Water quality constituent concentrations for the majority of parameters measured during 1997 were within the established ranges historically associated with each site. For well 008-79-6, a trend appeared to be developing as new maximum total alkalinity value was recorded • in September for both 1995 and 1996. This developing trend did not continue into 1997. However, in 2